Resize Image without losing quality

Question

I\'m using the functions below to resize my images width & height but I noticed that it ruins the image quality.

class func imageWithSize(image: UIImage,         


        

Answer 1

func image(image:UIImage,imageSize:CGSize)->UIImage
{
    UIGraphicsBeginImageContextWithOptions(imageSize, false, 0.0)
    [image .drawInRect(CGRectMake(0, 3, imageSize.width, imageSize.height))]
    let newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext()
    return newImage;
}